Drawer unit, and image forming apparatus using the drawer unit

Abstract

A drawer unit including a housing and a drawer inserted into the housing in inserting direction and drawn therefrom in drawing direction is provided. A locking member is mounted on the housing or the drawer to extend in direction intersecting the inserting direction, and is rotatable on a rotating shaft extending in the inserting direction such that when the drawer is inserted, the locking member rotates from unlock position to lock position in locking direction while rotating from the lock position to the unlock position in unlocking direction prior to drawing of the drawer. A locking wall and a pushing wall are mounted on the other of the housing and the drawer. The locking member in the lock position is engaged with the locking wall. When being rotated in the unlocking direction, the locking member is contacted with the pushing wall, which pushes the drawer in the drawing direction.

What is claimed is: 
     
       1. A drawer unit comprising:
 a housing; 
 a drawer, insertable into the housing in an inserting direction and configured to be drawn from the housing in a drawing direction opposite to the inserting direction; 
 a locking member mounted on one of the housing and the drawer; and 
 a locking wall and a pushing wall, mounted on another of the housing and the drawer on which the locking member is not mounted, 
 wherein the locking member extends in a direction intersecting the inserting direction, and is rotatable on a rotating shaft extending in the inserting direction in such a manner that when the drawer is inserted into the housing, the locking member rotates from an unlock position to a lock position in a locking direction, the locking member being rotatable from the lock position to the unlock position in a first unlocking direction prior to drawing of the drawer from the housing, wherein when the locking member is in the lock position, the locking member is engaged with the locking wall, and wherein when the locking member is rotated in the first unlocking direction, the locking member is contacted with the pushing wall, and the pushing wall is inclined to the drawing direction so as to push the drawer in the drawing direction as the locking member rotates in the unlocking direction. 
 
     
     
       2. The drawer unit according to  claim 1 , further comprising:
 a drawing wall mounted on the another of the housing and the drawer, wherein the drawing wall is located on an upstream side from the locking wall relative to the locking direction so as to be adjacent to the locking wall, and wherein when the locking member is rotated in the locking direction, the locking member is contacted with the drawing wall, and the drawing wall draws the drawer in the inserting direction as the locking member rotates. 
 
     
     
       3. The drawer unit according to  claim 1 , wherein the housing serves as part of an image forming apparatus in which a toner image is formed on a surface of a recording medium sheet, and one or more of constituent parts of the image forming apparatus are mounted on the drawer, wherein the locking member is rotatable in a second unlocking direction opposite to the first unlocking direction, wherein a rotation angle at which the locking member is rotated from the lock position to the unlock position via the pushing wall in the first unlocking direction is relatively larger than a rotation angle at which the locking member is rotated from the lock position to the unlock position in the second unlocking direction, wherein when the recording medium sheet jams in the image forming apparatus, the locking member is rotated in the first unlocking direction to unlock the drawer, and wherein the locking member is rotated in the second unlocking direction to unlock the drawer in a case other than jamming of the recording medium sheet. 
     
     
       4. The drawer unit according to  claim 1 , further comprising:
 a drive member to drive the locking member to rotate; and 
 a drive controller to control the drive member such that when the drawer is inserted into the housing, the locking member rotates from the unlock position to the lock position in the locking direction while the locking member rotates from the lock position to the unlock position in the first unlocking direction prior to drawing of the drawer from the housing. 
 
     
     
       5. The drawer unit according to  claim 4 , wherein the housing serves as part of an image forming apparatus in which a toner image is formed on a surface of a recording medium sheet, and one or more of constituent parts of the image forming apparatus are mounted on the drawer, wherein the recording medium sheet jams in the image forming apparatus, the image forming apparatus resolves jamming by performing plural processes including a process of drawing the drawer, and wherein the drive controller controls the drive member to rotate the locking member from the lock position to the unlock position in the process of drawing the drawer. 
     
     
       6. The drawer unit according to  claim 1 , wherein the locking member is mounted on the drawer, and the locking wall and the pushing wall are mounted on the housing. 
     
     
       7. The drawer unit according to  claim 6 , wherein the locking wall is located in front of the locking member having the lock position relative to the drawing direction, and the pushing wall is located in front of the locking wall relative to the inserting direction while slanting in the drawing direction relative to the first unlocking direction. 
     
     
       8. The drawer unit according to  claim 6 , further comprising:
 a drawing wall mounted on the housing, wherein the drawing wall is located on an upstream side from the locking wall relative to the locking direction so as to be adjacent to the locking wall, wherein when the locking member is rotated in the locking direction, the locking member is contacted with the drawing wall, and the drawing wall draws the drawer in the inserting direction as the locking member rotates, and wherein the drawing wall is connected with the locking wall while slanting in the inserting direction relative to the locking direction. 
 
     
     
       9. The drawer unit according to  claim 1 , further comprising:
 a first sensor, mounted on the housing to detect the drawer located at an insertion position at which the drawer is completely inserted into the housing; and 
 a second sensor, mounted on the housing to detect the drawer located at a distant position, apart from the insertion position at which the drawer is completely inserted into the housing, at a distance in the drawing direction. 
 
     
     
       10. An image forming apparatus comprising:
 image forming members to form and fix a toner image on a recording medium sheet; and 
 the drawer unit according to  claim 1 , wherein one or more of the image forming members are mounted on the drawer unit. 
 
     
     
       11. An image forming apparatus comprising:
 image forming members to form and fix a toner image on the recording medium sheet; and 
 the drawer unit according to  claim 3 , wherein one or more of the image forming members are mounted on the drawer unit. 
 
     
     
       12. An image forming apparatus comprising:
 image forming members to form and fix a toner image on a recording medium sheet; and 
 the drawer unit according to  claim 6 , wherein one or more of the image forming members are mounted on the drawer unit. 
 
     
     
       13. An image forming apparatus comprising:
 image forming members to form and fix a toner image on the recording medium sheet; and 
 the drawer unit according to  claim 8 , wherein one or more of the image forming members are mounted on the drawer unit. 
 
     
     
       14. The drawer unit according to  claim 1 , wherein the housing serves as part of an image forming apparatus in which a toner image is formed on a surface of a recording medium sheet, wherein the locking member is rotatable in a second unlocking direction opposite to the first unlocking direction, and wherein when the recording medium sheet jams in the image forming apparatus, the locking member is rotated in the first unlocking direction to unlock the drawer, and wherein the locking member is rotated in the second unlocking direction to unlock the drawer in a case other than jamming of the recording medium sheet. 
     
     
       15. An image forming apparatus comprising:
 image forming members to form and fix a toner image on the recording medium sheet; and 
 the drawer unit according to  claim 14 , wherein one or more of the image forming members are mounted on the drawer unit. 
 
     
     
       16. The drawer unit according to  claim 1 , further comprising:
 a drawing wall mounted on the housing, wherein the drawing wall is located on an upstream side from the locking wall relative to the locking direction so as to be adjacent to the locking wall, wherein when the locking member is rotated in the locking direction, the locking member is contacted with the drawing wall, and the drawing wall draws the drawer in the inserting direction as the locking member rotates, and wherein the drawing wall is connected with the locking wall while slanting in the inserting direction relative to the locking direction. 
 
     
     
       17. An image forming apparatus comprising:
 image forming members to form and fix a toner image on a recording medium sheet; and 
 the drawer unit according to  claim 16 , wherein one or more of the image forming members are mounted on the drawer unit.